Introduced in 1969, the Seiko Speedtimer was a major innovation milestone – the world’s first automatic chronograph watch with column wheel and vertical clutch, still prerequisite in high functionality chronographs for accurately measuring elapsed time. The hard-coated bezel ...Introduced in 1969, the Seiko Speedtimer was a major innovation milestone – the world’s first automatic chronograph watch with column wheel and vertical clutch, still prerequisite in high functionality chronographs for accurately measuring elapsed time. The hard-coated bezel features a tachymeter speed measurement tool.
Under dual-curved sapphire glass, the sub dials contrast the black dial for legibility with a different finish. Powered by the in-house 8R48 mechanical chronograph calibre, this movement allows accurate measurement of elapsed time by combining a vertical clutch and a column wheel in a 49.5 mm lug to lug, 42mm diameter case size. The 8R watch movement series has been designed by Seiko for maximum precision with 3 key elements: 1) The Vertical clutch – eliminates shuddering or jumping of the hands when the start/stop button is pushed, enhancing the chronograph’s accuracy and durability 2) The Column wheel – resembles the top of a castle turret, ensures precise control of chronograph operation 3) The 3-pointed hammer – ensures that when the re-set pusher is pressed, all hands return to zero instantly, in perfect synchronisation for high durability Prospex is a combination of the words ‘Professional’ and ‘Specifications.’ Seiko Prospex timepieces are designed to be practical, reliable and durable; to meet the high standards required in extreme environments for sports lovers and adventure seekers alike.